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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
IAEA again raises global nuclear power projections
Noting recent momentum behind nuclear power, the International Atomic Energy Agency has revised up its projections for the expansion of nuclear power, estimating that global nuclear operational capacity will more than double by 2050—reaching 2.6 times the 2024 level—with small modular reactors expected to play a pivotal role in this high-case scenario.
IAEA director general Rafael Mariano Grossi announced the new projections, contained in the annual report Energy, Electricity, and Nuclear Power Estimates for the Period up to 2050 at the 69th IAEA General Conference in Vienna.
In the report’s high-case scenario, nuclear electrical generating capacity is projected to increase to from 377 GW at the end of 2024 to 992 GW by 2050. In a low-case scenario, capacity rises 50 percent, compared with 2024, to 561 GW. SMRs are projected to account for 24 percent of the new capacity added in the high case and for 5 percent in the low case.
G. C. Pomraning
Nuclear Science and Engineering | Volume 21 | Number 1 | January 1965 | Pages 62-78
Technical Paper | doi.org/10.13182/NSE65-A21016
Articles are hosted by Taylor and Francis Online.
A diffusion theory for the asymptotic transport scalar flux is derived from the monoenergetic transport equation in slab geometry. By allowing the scalar flux to be discontinuous at a material property and/or an external-source discontinuity, the theory is able to predict exact asymptotic transport-theory behavior for two standard halfspace problems. A supplementary diffusion-like theory is developed to treat the non-asymptotic flux. The total (asymptotic plus non-asymptotic) formalism yields a continuous scalar flux distribution and gives exact transport -theory leakage from a halfspace with a spatially-constant source. Numerous numerical comparisons indicate that the theory proposed here is significantly more accurate than classical (P1) diffusion theory. The complexity of both the asymptotic and non-asymptotic formalisms is comparable with that of the P1 method. Finally, the entire formalism is generalized to three dimensions in rectilinear- and curvilinear-coordinate systems.
